Create Quad Meshes plug-in available on Food4Rhino

@Et_Rec,

the easiest way to find out is to make a mesh object from your geometry in Rhino using the _Mesh command using the desired settings. This way you see the mesh and can inspect it, before exporting it in STL format.

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I’m interested in this from a structural engineering perspective, we conduct finite element analysis that requires well formed quad meshes for accuracy. Unfortunately these algorithms do not appear to be very well suited as I get poor results when trying to mesh a simple planar rectangle. They must be tuned for meshing the surfaces of complex volumes.

If I am simply not configuring the solver correctly please let me know!

If anyone was able to point me in the direction of a Rhino (preferably Grasshopper) based mesher I would be very interested. The best I have found is Millipede, although this only produces triangle meshes (which are acceptable, but quads are preferable).

A decent FEA meshing capability in Rhino would make the product even more attractive to structural engineering consultancies!

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That’s great work! Just some nitpicking, as you asked for feedback :o) Purely algorithmic conversions sure do produce quad meshes – but (against popular belief) this fact alone doesn’t them superior for rendering and UV-Work or even good input for SubD modeling.

To yield more suitable topology for further processing, other software implementations combine similar algorythms with sketching on the input mesh, similar to the way one lays out surfaces in Reverse Engineering software.This forces the mesher to create a mesh which Catmull-Clark subdividable and which follows closely the design intent. Here’s a sample video showing how this works elsewhere. It’s often impractical to rework a purely software created mesh to a human editable mesh – one really needs to think of this right from the beginning.

From a SubD modeling standpoint the face-count of output meshes in all the demonstrated cases is unneccesarily high (which has exactly the same drawbacks as Nurbs modeling with needlessly dense surfaces). That’s another reason why one should strive for the Catmull-Clark scheme. These meshes may get represented as very loose and easily editable cages but when subdivided (or transfered to Limit Surfaces) and reprojected to the Input mesh, they may hold a lot of detail.

I sketched over a mesh version which contain a few features in the mesh flow which really have to be in there, right from the start to obtain a model which can get further refined with SubD methods.

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If you’re trying Instant Meshes on an open plane, or open anything you need to make sure Align to Boundaries is checked and Fill Holes is unchecked.

@Et_Rec try setting all of the input boxes to 0 and Maximum Distance Edge to Surface to .002. Leave Refine Mesh checked. This will provide plenty of resolution to avoid faceted looking prints as well as keep file sizes in check. You should see file sizes between 3 to 20 mb depending the amount of rounded prongs or spherical milgrain in the model.

Thanks Travis, that definitely helps a lot. Unfortunately some simple shapes still dont mesh satisfactorily (do not meet the original edges). Looks like I am trying to use this tool in a way that it was not developed for!

Thanks Trav. I will try your settings out. I probably should have started this discussion in a new topic. No one seems to answer my original question. Can this plugin be of help to someone printing jewelry sized objects?

You would not need this plug-in to help you print jewelry models, no.

If your source model is a Nurbs object I see no advantage whatsoever in turning it to Quads for 3D printing.

There’s no doubt that both meshing routines prefer closed meshes however i think in this case, the default smoothing value of 2 is contributing to the relaxing of the quads in the image you posted. When Smoothing steps is set to 0 things improve. I also think there’s room to improve and optimize the fit of the quad mesh back to the original input object with some further work.

I believe that mesh files made by the CreateQuadMesh plugin are smaller than mesh files made by the Mesh command. Another advantage of the CreateQuadMesh plugin is that inexperienced Rhino users sometimes make meshes made of sliver-shaped faces which 3D printers cannot process.

For a long time one could only feed triangulated meshes as .stl files to 3D print software. Some programs now also accept quad meshes but I would not be surprised if they still triangulated them internally…

Generally I think Rhinos default Mesher is far more suitable for 3D-printing and should usually create smaller meshes too. Good SubD-meshes by definition have to have a more or less uniform density everywhere: While Rhinos Mesher can save polygons on areas with little curvature and even can close a planar surface in the Nurbs model with two triangles both quad-remesher types will create needless geometry on planar faces (needless for the purpose of 3D printing).

Generally remeshing based on the render mesh (as used by the Plugin discussed here) can not be as accurate as creating the mesh based on the surface model.

The CreateQuadMesh plugin has two algorithms: Instant Mesh and Quadriflow.

Quadriflow is well suited for organic objects and SubD objects, but it is slow and cannot make good, sharp edges. For example, if the original object is a cylinder, Quadriflow makes mesh cylinder with rugged edges.

Instant Mesh is faster than Quadriflow. Its default weld angle of 180 also makes rugged edges. Reducing the weld angle by half greatly improves the edges of the cylinder.

I’m confused. Were you now answering me or is this rather a note to yourself?

I believe that you are correct because there is a bug in the CreateQuadMesh plugin - the plugin makes more or less square mesh faces regardless of the grid aspect ratio setting.

That is not a bug. For SubD modelling an even mesh layout is mandatory and it is very desirable to have mostly square mesh faces.

Those settings are currently not connected. The plug-in utilizes the render mesh as shown in the video posted above. This was part of the test harness that should be either removed or expanded from the test plug-in.

I think there is some confusion. The setting for sharp tells Quadriflow to respect a sharp edge in the remeshing algorithm so that edge stays in place. If the resulting quadmesh is then imported, the sharp edges are “welded” to say it in Rhino slang. You’ll need to use _Unweld to correct this.

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Yes, we are confused.

Hi @dale,
do you have any thoughts on this? Curves to control the mesh flow* isn’t some creamtopping for nerds – one need them to help those algorythms build an editable mesh. The remeshing results shown in the video clip are not suitable for SubD-Modeling.

*on Surface Models one could often use existing Edges as guides.


One crucial thing I forgot yesterday is symmetry support: In the case of the ornament in Brians clip one should be able to cut down the meshers work by defining a symmetry plane. The output mesh would be a lot cleaner. Diamond shaped mesh faces across the symmetry plane symmetry plane should get avoided.

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